/* nag_regress_confid_interval (g02cbc) Example Program.
 *
 * Copyright 1992 Numerical Algorithms Group.
 *
 * Mark 3, 1992.
 * Mark 8 revised, 2004.
 */

#include <nag.h>
#include <stdio.h>
#include <nag_stdlib.h>
#include <nagg02.h>

int main(void)
{
  Integer exit_status=0, i, n;
  NagError fail;
  Nag_SumSquare mean;
  char m, w;
  double clm, clp, *h=0, *res=0, rms, *wt=0, *x=0, *y=0, *yhat=0, *yl=0, *yml=0;
  double *ymu=0, *yu=0;

  INIT_FAIL(fail);

  Vprintf("nag_regress_confid_interval (g02cbc) Example Program Results\n");
  /* Skip heading in data file */
  Vscanf("%*[^\n]");
  Vscanf("%ld\n",&n);
  Vscanf("%lf%lf\n",&clm,&clp);
  Vscanf(" %c %c\n",&m,&w);
  if (n>=(m == 'M' || m == 'm' ? 2 : 1) )
    {
      if ( !( x = NAG_ALLOC(n, double)) ||
           !( y = NAG_ALLOC(n, double)) ||
           !( wt = NAG_ALLOC(n, double)) ||
           !( yhat = NAG_ALLOC(n, double)) ||
           !( yml = NAG_ALLOC(n, double)) ||
           !( ymu = NAG_ALLOC(n, double)) ||
           !( yl = NAG_ALLOC(n, double)) ||
           !( yu = NAG_ALLOC(n, double)) ||
           !( h = NAG_ALLOC(n, double)) ||
           !( res = NAG_ALLOC(n, double))
           )
        {
          Vprintf("Allocation failure\n");
          exit_status = -1;
          goto END;
        }
    }
  else
    {
      Vprintf("Invalid n.\n");
      exit_status = 1;
      return exit_status;
    }
  if (m == 'm' || m == 'M')
    mean = Nag_AboutMean;
  else if (m == 'z'|| m == 'Z')
    mean = Nag_AboutZero;
  if (w == 'w' || w == 'W')
    for (i=0; i<n; i++)
      Vscanf("%lf%lf%lf\n",&x[i],&y[i],&wt[i]);
  else
    for (i = 0; i < n; ++i)
      Vscanf("%lf%lf\n",&x[i],&y[i]);

  /* nag_regress_confid_interval (g02cbc).
   * Simple linear regression confidence intervals for the
   * regression line and individual points
   */
  nag_regress_confid_interval(mean, n, x, y, wt, clm, clp, yhat, yml, ymu, yl,
                              yu, h, res, &rms, &fail);
  if (fail.code != NE_NOERROR)
    {
      Vprintf("Error from nag_regress_confid_interval (g02cbc).\n%s\n",
              fail.message);
      exit_status = 1;
      goto END;
    }

  Vprintf("\ni       yhat[i]    yml[i]    ymu[i]      yl[i]      yu[i]"
          " \n\n");
  for (i=0; i < n; ++i) {
    Vprintf("%ld %10.2f %10.2f", i, yhat[i], yml[i]);
    Vprintf("%10.2f  %10.2f %10.2f\n",ymu[i], yl[i], yu[i]);
  }
 END:
  if (x) NAG_FREE(x);
  if (y) NAG_FREE(y);
  if (wt) NAG_FREE(wt);
  if (yhat) NAG_FREE(yhat);
  if (yml) NAG_FREE(yml);
  if (ymu) NAG_FREE(ymu);
  if (yl) NAG_FREE(yl);
  if (yu) NAG_FREE(yu);
  if (h) NAG_FREE(h);
  if (res) NAG_FREE(res);
  return exit_status;
}